May 5, 2009

Mothers, Newborns Have Vitamin D Deficiency

Investigators report that over one third of mothers and half of their infants have vitamin D deficiency at the time of birth.

Prenatal vitamin D supplements do not fully protect against this deficiency, according to data released at the Pediatric Academic Societies annual meeting.

The Director of the Breastfeeding Center at Boston Medical Center, Anne Merewood, and her associates took measurements of vitamin D levels in 433 women and 376 newborns by using blood samples obtained within 72 hours of birth. Also, they collected data from questionnaires completed by the mothers and from the mother's medical records.

Vitamin D deficiency was present in 36 percent of the mothers and 58 percent of the babies in the results. In roughly two-thirds of the cases, the deficiency was classified as severe.

The women who took the vitamin D prenatally five or more times a week during the third trimester had over 30 percent deficiency at the time they gave birth.

The women that were vitamin D deficient at the time of birth were over five times more likely to have an infant with vitamin D deficiency as women who were not vitamin D deficient.

Merewood called for measures to ensure that women of childbearing age maintain an adequate vitamin D intake. "The most obvious way to correct deficiency is sensible sun exposure," she said. "While a sunburn should be avoided, even a small amount of time spent outdoors was protective against deficiency."

She said that other vitamin D sources include cod liver oil tablets, vitamin D fortified milk, and fatty fish.

The results need to be interpreted cautiously, given the ongoing debate among experts on the definition of vitamin D deficiency, according to the Boston Researchers.

She explained that there are not many children that are technically classified as vitamin D deficient and have any apparent physical signs of deficiency. "More research is needed to determine the exact definition of deficiency, especially in children."